Rather than counting calories, she trades high-glycaemic options for low-glycaemic alternatives.

One of her favourite dishes, she reveals, is sesame-crusted seared ahi tuna with Japanese soba noodles and a salad.

'Besides being delicious and healthy, the whole dinner cooks in one minute,' she said.

'I sear the tune 30 seconds on each side and the noodles take another minute to boil. Because they are buckwheat, a complex carbohydrate, they are lower in carbs than white noodles. The most time is spent on making the salad.'

'Another favorite dinner I love to make is fish tacos with low-carb tortillas,' she added. 'My husband Michael grills the fish and then we season them with onion, lime and cilantro – delicious.'

Mrs Feinstein has now written a book, titled 2-3-4 Weight Loss Solution, about her diet, with, of course, an accompanying recipe guide.

In addition to her healthy eating regime, it also details a spiritual approach to health she has embraced after studying complementary and alternative medicine.

She credits it with helping her understand her 'food triggers', and hails meditation as the 'secret ingredient' in her transformation.